Memory devices are typically provided as internal, semiconductor, integrated circuits in computers or other electronic devices. There are many different types of memory including random-access memory (RAM), read only memory (ROM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), and flash memory.
Flash memory devices have developed into a popular source of non-volatile memory for a wide range of electronic applications. Flash memory devices typically use a one-transistor memory cell that allows for high memory densities, high reliability, and low power consumption. Common uses for flash memory include personal computers, personal digital assistants (PDAs), digital cameras, and cellular telephones. Program code and system data such as a basic input/output system (BIOS) are typically stored in flash memory devices for use in personal computer systems.
Flash memory devices typically use fuse elements for storing control, trimming, and/or operational status data. For example, lock bits might be stored in a mini-array of fuse elements to indicate when a block of flash memory is write protected.
Typically, fuses in non-volatile memory designs employ a single core cell as the fusible element. This fusible element has substantially the same reliability as the main memory array.
As with other memory devices, defects can occur during the manufacture of a flash memory array having rows and columns of memory cells. Typical defects can include bad memory cells, open circuits, charge loss or gain, shorting between bitlines (columns), and shorting between wordlines (rows). Short conditions typically occur because of the large number of rows and columns of memory cells that have to be placed in close proximity to each other on an integrated circuit. Defects can reduce the yield of the flash memory device. In fact, some short conditions may cause the device to be useless.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for reducing or eliminating the problems associated with a short or other defect in a memory device.